Equipment disconnect required in C1D2 space?

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greenspark1

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New England
Hi all. Outdoors in a C1D2 area I have a skid mounted piece of 480V pre-manufactured equipment consisting of two 45 kW resistance heaters, a couple small motors (<5hp), and some ancillary controls. It is fed by a dedicated feeder from a panelboard breaker indoors out of sight. Once at the skid power is split and protection provided for each piece of equipment: each heater with fuses, CBs for the motors, and fuses for the controls. The question is if the whole assembly requires a primary disconnecting means outdoors at the equipment.

I intend to use the breaker as the disconnecting means but am looking for any Code requirements otherwise. There are separate CBs for the motors on the skid. I don't believe the equipment falls under 430 since the motors are relatively minor. 424.19 does not require the disconnecting means to be within sight of the unit. Especially since this is C1D2, I'd like to keep redundant disconnects out of the area.
 
Is the interior panelboard breaker lockable (able to meet LOTO requirements?)
Is there a plug and receptacle connection (non load breaking) or is it hard wired?
 
A few comments:

? Unless the entire skid mounted assembly is listed as a whole, the basic rules of the NEC apply.
? Article 424 only applies to space heating. Article 427 applies to process heating.
? Five hp isn't minor; Sections 430.102 to 113 even apply to fractional hp motors. Section 430.102 (B) Ex to (1) and (2) is of specific interest. See FPN/IN No. 1 for some additional points.​
 
greenspark1 said:
Hi all. Outdoors in a C1D2 area I have a skid mounted piece of 480V pre-manufactured equipment consisting of two 45 kW resistance heaters, a couple small motors (<5hp), and some ancillary controls. It is fed by a dedicated feeder from a panelboard breaker indoors out of sight. Once at the skid power is split and protection provided for each piece of equipment: each heater with fuses, CBs for the motors, and fuses for the controls. The question is if the whole assembly requires a primary disconnecting means outdoors at the equipment.

I intend to use the breaker as the disconnecting means but am looking for any Code requirements otherwise. There are separate CBs for the motors on the skid. I don't believe the equipment falls under 430 since the motors are relatively minor. 424.19 does not require the disconnecting means to be within sight of the unit. Especially since this is C1D2, I'd like to keep redundant disconnects out of the area.
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Just my opinion here.

The code does not require a feeder have a disconnecting means "in sight" of the equipment.

There are required disconnecting means for various pieces of equipment (heaters, motors, etc.) found in the respective sections of the code.

I don't think the size of the motors is relevant. The rules are essentially the same.

The rules are not different for classified areas, although there is a FPN that suggests one of the exceptions can always be taken in such an area.

ETA: Just curious how they are handling the skid mounted CB for each motor. Are they located in an XP enclosure of some sort? An XP combination starter?
 
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